| 摘要 |
PURPOSE:To obtain a semiconductor device conducting a highspeed operation by a method wherein an outside base region having a high impurity concentration, which is provided in the proximity of an active base region, is formed in a self-alighnment manner, and the inclusion of an impurity of a different conductivity type into the emitter region is prevented by an insulating film. CONSTITUTION:An N<+> type burried layer 203 is formed on a P type Si substrate 201 such that one end portion of the layer 203 is exposed to the surface. The periphery of a flat portion of the layer 203 is surrounded by a P<+> type channel stopper region 202. An N type layer 204 is epitaxitially grown on the flat portion of the layer 203, which becomes an insular configuration by virtue of an interelement separation oxide film 205. A P<-> type base layer 206 is diffusion-formed on a surface layer portion of the layer 204 and a recessed portion is provided at a central portion of the surface thereof. Thereafter, the periphery of the recessed portion and a layer 203 exposed to the surface are overlaid with a laminate composed of a polycrystalline Si layer 207 and an Si3N4 film 208. A P<+> type outside base region 212, whichis squeezed into a layer 204 at the recessed portion by means of ion implantation, and an N<+> type emitter region 214 in the vicinity of the region 212 are formed, thus reducing the base resistance and eliminating the need for a compensation of impurity in relation to the emitter region. |
